document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=152487>Question 152487</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hi,\r<BR>\n" );
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document.write( "How would I solve the following: Applications of Linear Equations \r<BR>\n" );
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document.write( "Walt made an extra $9000 last year from a part-time job. He invested part of the money at 9% and the rest at 8%. He made a total of $770 in interest. How much was invested at 8%?\r<BR>\n" );
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document.write( "Thank you for taking the time to help me.\r<BR>\n" );
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document.write( "Sally </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #112076 by </B><A HREF=/tutors/aboutme.mpl?userid=Earlsdon><B>Earlsdon(6294)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Earlsdon><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=112076\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> G'day Sally;\r<BR>\n" );
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document.write( "Let x = the amount invested at 8% and the remainder ($9000-x) is invested at 9%<BR>\n" );
document.write( "The amount of interest earned on these amounts can be expressed as:<BR>\n" );
document.write( "x(0.08) This is amount earned at 8%.<BR>\n" );
document.write( "($9000-x)(0.09) This is the amount earned at 9%<BR>\n" );
document.write( "The sum (+) of these two amounts is given as $770.00, so you can write the equation to solve for x, the amount invested at 8%<BR>\n" );
document.write( "(0.08)x + (0.09)($9000-x) = $770  Simplify and solve for x.<BR>\n" );
document.write( "0.08x + $810 - 0.09x = $770 Subtract $810 from both sides.<BR>\n" );
document.write( "0.08x-0.09x = -$40 Combine the x's on the left side.<BR>\n" );
document.write( "-0.01x = -$40 Finally, divide both sides by -0.01 to get x by itself.<BR>\n" );
document.write( "x = $4000<BR>\n" );
document.write( "So $4000 was invested at 8% and $9000-$4000 = $5000 was invested at 9%\r<BR>\n" );
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document.write( "Let's check the solution:<BR>\n" );
document.write( "0.08($4000) + 0.09($5000) = $320 + $450 = $770 The total interest earned. </SPAN>\n" );
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